Extension-ladder.



P. B. JOHNSON & E. ANDERSON.

. EXTENSION LADDER. APPLIGA'TION FILED JULY 2,1914.

Patented Nov. 3, 1914.

Unirrn strarss PATENT OFFICE.

PEER EDWARD JOHNSON AND EDWARD ANDERSON, OF NEW YORK, N. Y.

' EXTENSION-LADDER.

Specification of Letters Patent.

Patented Nov. 3, 1914.

To all whom it may concern Be it known that we, PHER EDWARD J OHN- SON and EDWARD ANDERSON, bot-h citizensof the United States, and residents of the c1ty of New York, borough of Brooklyn, in the county of Kings and State of New York, have invented a new and Improved Extension-Ladder, of which the following is a full, clear, and exact description.

The object of the invention is to provide a new and improved ladder capable of being extended in a very simple and secure manner.

In order to accomplish the desired result,

use is made of extension side pieces connected with each other by adjustable rungs or steps and adjustably secured to the main side pieces of the ladder.

A practical embodiment of the invention is represented in the accompanying drawings forming a part of this specification, in which similar characters of reference indi' cate corresponding parts in all the views.

Figure 1 is a perspective view of a double.

ladder provided with the extension device; Fig. 2 is an enlarged sectional plan view of part of the same on the line 2+2 of Fig. 1; Fig. 3 is a sectional side elevation of the same on the line 3-3 of Fig. 2; Fig. 4 is a face view of one of the connecting parts of one of the clamps; and Fig. 5 is an enlarged sectional plan view of the extension device on the line 5-5 of Fig. 1.

The improvement is shown applied to a double ladder, that is, one formed of two ladders A and B, connected with each other at their upper ends by hinges C so that one ladder forms a prop for the other when the ladders are in extended position. The hinges G permit of folding the ladders one on top of the other when the double ladder is to be stored and not in use. As the extension device is the same foreach ladder A and it suffices to describe but one in detail, es eciall'y as the extension device may be use on a single ladder.

The side pieces or rails-D, D of each ladder A and B are rigidly connected with each other by rungs E and onto the outer faces of the said side pieces D, D fit extension side pieces or rails F, F fastened in position on the said main side pieces D, D by clamps G, preferably two for each extension side piece F and F. The clamp G is provided with bars G, Gr having angular members G, G slidably fitting one on the other so as to permit using the clamp G on side pieces- D, F and D, F of difl'erent width. The

members G and G are slidably connected with each other by a rivet H having countersunk heads H, H of which the latter slidingly fits into a groove in the member G and the shank H of the shaft H engages a slot in the member G as indicated in dotted lines in Fig. 2. The member Gr fits against the inner face of the corresponding side piece D or D. The bars G, G extend 5 across the front and rear of the side pieces D, F or D, F, and terminate in threaded rods G connected with each other by a bar it forced against the outer face of the corresponding extension side piece F or F by wing nuts G screwing on the threaded portions o-fthe rods G, as will be readily understood by reference to Figs. 2 and 3. The inner face G of the connectingbar G is roughened so as to firmly engage the outer face of the corresponding side piece F or F. The rods G extend through slots G in the connecting bar G to allow of using the clamp on side pieces D, F and D, F of different width. By the arrangement described, the extension side pieces Fand F can be securely clamped to the main side pieces D and D" of the ladder A or B, so that the ladder is increased in length.

The extension side pieces F, F are provided with removable and adjustable su plementary rungs I to permit the user of the ladder to conveniently reach the main rungs E when going up t e ladder. plementary rung I is formed of two telescoping members I and I adapted to be fastened together by a set screw I Ssee Figs. 1 and 5). The outer ends of the te escoping members I and I terminate in U-shaped heads I, I adapted to straddle the extension side pieces F and F, as plainly indicated in Figs. -1 and 5 The outer members of the heads I, I are provided with clamping screws I, Iadapted to engage the outer faces of the extension pieces F and F while inner members of the'heads I, I engage the inner faces of the side extension .side pieces F and F. The inner members of the heads I, I are preferably roughened, as indicated at I so that the heads take firm hold on the extension side pieces wheneverthe clamping screws 1, I are screwed up to securely hold the rungs in position on the extension side pieces F and F. By making the rungs extensible they can be readily Each sup- 7 the rungs I can be adjusted up or down on ,ing the said extension main side pieces each clamp having L-sha Jedthe said extension side pieces to space the auxiliary rungs 1 approximately the same distance apart as the fixed rungs E, and to space the uppermost auxiliary rung I the desired distance apart from the lowermost fixed rung E.

It will be noticed that a ladder provided.

with the extension device shown and described is a true extension ladder in that it has side pieces as Well as rungs I the same as the regular ladder.

.When the extension device is not to be used it can be readily detached from the ladder A or B by removing the clamps G, and the extension device can be readily packed into a small bundle by disconnecting the auxiliary rungs I from the side pieces F and F.

Having thus described our invention, we claim as new and desire to secure by Letters Patent:

1. A ladder, comprising main side pieces, rungs rigidly connecting the said main side pieces with each other, extension side pieces fitting against the outer faces of the said main side pieces, clamps adjustably fasten side pieces to the said members slidably mounted one on the ot er to fit side pieces of di'fierent width, theclamp members terminating in threaded rods, a connecting bar having slots for the passage of the rods to connect the" latter with the connecting bar fitting around the outer face of the corresponding extension side piece, and nuts screwing on the said rods against the connecting bar.

2. A ladder, comprising main side pieces, rungs rigidly connecting the said main side pieces with each other, extension side pieces fitting against the outer faces of the said main side pieces, clamps adjustably fastenin the said extension slde nieces to the main si e pieces, each clamp having L-shaped members slidably mounted one on the other to fit side ieces, of different width, the clamp meml ers terminating in threaded rods, a connecting bar having slots for the passage of the rods to connect the latter with the connecting bar fitting against the outer face of the side piece, the inner face of the connecting bar being roughened, and nuts screwrng on the said rods against the connecting. bar.

3. A ladder provided with a rung made in telescoping sections, each terminating at its outer end in an integral U-shaped clamping head adapted to straddle a side piece of the ladder, one member of the head fitting against one face of the corresponding side piece, and a clamping screw screwing 1n the other member against the other face of the said correspondin side piece.

In testimony wh names to this specification in the presence of two subscribing witnesses.

PHER EDWARD JOHNSON. EDWARD ANDERSON. \Vitnesses BRAXTON B. RICHARDSON, S. E. ALLEN REHNTRON.

corresponding extension ereof we have signed our 

